PwnageTool is described as 'advanced jailbreaking application by the iPhone Dev Team for Mac OS X. It can build a pre-jailbroken .ipsw ("iPhone software") file with apps and anything else pre-loaded, so that you can run apps without the approval of Apple'. There are eight alternatives to PwnageTool for iPhone, iPad, Mac, Windows and Linux. The best alternative is 3uTools. It's not free, so if you're looking for a free alternative, you could try checkra1n or Animate. Other great apps like PwnageTool are Ultrasn0w (Free), BootNeuter (Free), Blacksn0w (Free) and unc0ver (Free).
3uTools is the most efficient iOS file and data management tool for Apple users. 3uTools provides one-click downloads for iOS users with free genuine iOS apps, popular games, free ringtones, and HD wallpapers.
Blacksn0w unlocks your jailbroken iPhone, allowing it to be used with any GSM carrier (AT&T and TMobile in the U.S.) without a contract. It can be installed through blackra1n, the jailbreaking application by geohot.
unc0ver is a jailbreak, which means that you can have the freedom to do whatever you would like to do to your iOS device. Allowing you to change what you want and operate within your purview, unc0ver unlocks the true power of your iDevice.
seas0npass offers an easy way to jailbreak your Apple TV (2nd generation) running iOS 4.2. It downloads and jailbreaks a .ipsw file (iPhone software), which is then restored to your Apple TV through iTunes.